System for Control of Mobile Hydraulic Equipment

ABSTRACT

A controller for mobile hydraulic equipment includes a radio receiver, hydraulic controller, and display unit. The controller further includes terminals configurable to function as a combination of analog or digital inputs or outputs according to the system requirements. A user interface included on the controller permits an operator to select a desired function for each terminal and to configure the controller according to the application requirements.

BACKGROUND OF THE INVENTION

The subject matter disclosed herein relates to a controller for mobilehydraulic equipment. More specifically, the subject matter disclosedherein relates to an integrated radio receiver, hydraulic controller,and user interface with enhanced control.

Mobile hydraulic equipment, such as a boom and outriggers, may bemounted to or integrally assembled onto a vehicle frame to provide amobile crane. The mobile crane may then be driven to locations, such asconstruction sites, where heavy objects need to be moved. The componentsof the crane are often driven by hydraulic motors or pistons. Thehydraulic system may, for example, raise and lower, extend and retract,or rotate the boom during a lift. The hydraulic system may additionallybe required to extend and retract or raise and lower outriggers used tostabilize the vehicle. Further, a hydraulic motor may drive a winch usedto raise and lower the hook during a lift.

Each of the motions of the mobile crane may require different methods ofcontrol from the hydraulic system. Some of the motions may require, forexample, a binary on/off signal while other motions may require variableflow control. A hydraulic valve can be controlled by an electronicsolenoid either to supply hydraulic fluid to a component or to cause thehydraulic fluid to return to a reservoir. Further, the rate at which thefluid is supplied may affect the speed at which the component moves. Inone mode of operation, the solenoids may be selectively turned fully onor off to open or close the valve. Alternately, the solenoids may bemodulated on and off at a duty cycle to partially open a valve,controlling the rate at which the hydraulic fluid flows through thevalve.

Historically, the control of the hydraulic system has utilized a valveblock and a hydraulic controller to control each of the components ofthe mobile crane. The hydraulic controller receives command signalseither via separate electrical conductors or, optionally, via anindustrial network from a control device. The hydraulic controllerconverts the command signals to control signals for each solenoid tocontrol individual valves on the valve block.

The control device receives commands from an operator to select desiredmotions of the mobile crane. The control device may include pushbuttons,toggle switches, selector switches, levers, joysticks, or a combinationthereof, with which the operator may identify a desired motion and adesired speed of that motion. Typically the control device is a wirelessdevice which allows the operator to be positioned in proximity to or inview of the lift or other commanded motion. The wireless control devicenecessarily includes a transmitter, and a receiver is mounted on thevehicle to receive the command signals from the transmitter. Thereceiver passes the command signals from the transmitter to thehydraulic controller via either discrete wiring or via an industrialnetwork.

In addition, it is often desirable to provide the operator with a visualindication of the performance of the control system. Consequently, ahuman-machine interface (HMI) may also be included in the system. TheHMI is connected to the industrial network and monitors the commandsbetween the receiver and the hydraulic controller. The HMI may beconfigured to provide indicators of operation such as which motion isactive, the speed at which the motion is occurring, or fault conditionsin the system.

This method of controlling a mobile crane has not been met withoutvarious drawbacks. Each of the components of the control system, i.e.the hydraulic controller, receiver, and HMI, are typically provided byseparate vendors. Although each component may be ordered to meet adesired specification, the manufacturer of the mobile crane must manageintegration of each of the components. Further, different models andsizes of cranes may require different configurations for one or more ofthe components. Consequently, the mobile crane manufacturer may need tostock many different models or configurations of each component.Further, replacing certain members in the hydraulic system, such as apiston, may require adjustment to the control of the valve supplyinghydraulic fluid to the piston, which, in turn, requires recalibration ofthe control system.

Thus, it would be desirable to provide a controller which integratesmany of the control components, reducing the space required for multiplecomponents. Further, it would be desirable for the controller to beconfigurable for different applications, reducing the number and varietyof components required.

Another drawback of hydraulically operated mobile cranes is that thesame crane may often be required to operate in significantly variableenvironments. The crane may, for example, work outside or be driveninside a warehouse or manufacturing facility. Further, environmentalconditions in an outdoor environment may vary dramatically as theweather or seasons change. Significant changes in temperature may causethe viscosity of the hydraulic fluid to change, affecting its flow rateand the performance of the mobile crane.

Thus, it would also be desirable to compensate control of the hydraulicvalves according to the temperature of the environment in which thecrane is operating.

BRIEF DESCRIPTION OF THE INVENTION

The subject matter disclosed herein describes a controller for mobilehydraulic equipment including a radio receiver, hydraulic controller,and display unit. The controller further includes terminals configurableto function as a combination of analog or digital inputs or outputsaccording to the system requirements. A user interface included on thecontroller permits an operator to select a desired function for eachterminal and to configure the controller according to the applicationrequirements.

According to a first embodiment of the invention, a controller formobile hydraulic equipment includes a housing and a receiver mounted atleast partly within the housing. The receiver is configured towirelessly receive a plurality of transmitted control signals. Aprocessor mounted within the housing is operatively connected to thereceiver to receive the control signals and generate a plurality ofoutput signals for operating the mobile hydraulic equipment. A memorydevice mounted within the housing is operatively connected to theprocessor and stores at least one parameter corresponding to control ofthe mobile hydraulic equipment. A display mounted to the housing isoperatively connected to the processor. The display is configured toprovide a visual indication to an operator of at least one parametercorresponding to control of the mobile hydraulic equipment. A userinterface is mounted to the housing and configured to receive input fromthe operator to adjust the parameter on the display.

As another aspect of the invention, a plurality of terminals isoperatively connected to the processor and selectively configured tooperate in one of a plurality of modes. The memory device stores atleast one parameter corresponding to each terminal, and the parameter isadjustable from the user interface to select the operating mode.

Thus, it is a feature of this invention that a single controllerintegrates many of the control components for mobile hydraulic equipmentand provides flexibility to configure the controller according to therequirements of different applications.

As yet another aspect of the invention, a portion of the terminals maybe selectively operable in a first mode to receive an analog signal or asecond mode to receive a digital signal. A portion of the terminals mayalso be selectively operable in a first mode to receive an input signaland selectively operable in a second mode to transmit an output signal.In the first mode, the terminals may be selectively operable to receiveone of a digital input and a frequency input and, in the second mode, tooutput one of a current compensated output, a pulse width modulatedoutput, and a digital output. A portion of the terminals may beconfigured as paired outputs such that only one of the paired outputsmay output a signal at a time.

According to still other aspects of the invention, the user interfacemay be a plurality of buttons accessible to the operator through atleast one opening in the housing. A temperature sensor may provide asignal to the processor corresponding to an ambient temperature at thecontroller, and a portion of the terminals may be configured to providean output signal compensated as a function of the ambient temperature.

These and other objects, advantages, and features of the invention willbecome apparent to those skilled in the art from the detaileddescription and the accompanying drawings. It should be understood,however, that the detailed description and accompanying drawings, whileindicating preferred embodiments of the present invention, are given byway of illustration and not of limitation. Many changes andmodifications may be made within the scope of the present inventionwithout departing from the spirit thereof, and the invention includesall such modifications.

BRIEF DESCRIPTION OF THE DRAWING(S)

Various exemplary embodiments of the subject matter disclosed herein areillustrated in the accompanying drawings in which like referencenumerals represent like parts throughout, and in which:

FIG. 1 is a front elevation view of a controller according to oneembodiment of the invention;

FIG. 2 is a bottom plan view of the controller of FIG. 1

FIG. 3 is a schematic representation of an exemplary environmentincorporating the controller of FIG. 1;

FIG. 4 is a block diagram representation of the controller of FIG. 1;and

FIG. 5 illustrates one embodiment of a menu tree of parameters for thecontroller of FIG. 1

In describing the preferred embodiments of the invention which areillustrated in the drawings, specific terminology will be resorted tofor the sake of clarity. However, it is not intended that the inventionbe limited to the specific terms so selected and it is understood thateach specific term includes all technical equivalents which operate in asimilar manner to accomplish a similar purpose. For example, the word“connected,” “attached,” or terms similar thereto are often used. Theyare not limited to direct connection but include connection throughother elements where such connection is recognized as being equivalentby those skilled in the art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The various features and advantageous details of the subject matterdisclosed herein are explained more fully with reference to thenon-limiting embodiments described in detail in the followingdescription.

Referring initially to FIG. 1, a controller 10 for mobile hydraulicequipment includes a housing 12 having mounting feet 11 extendingoutwards from a rear surface of the housing 12. The mounting feet 11have a slot 13 or an opening 15 configured to receive a fastener, notshown, to secure the housing 12 to a mounting surface. The mountingsurface may be any surface on the vehicle to which the mobile hydraulicequipment is mounted or, optionally, the housing 12 may be mountedwithin a separate enclosure, not shown, which is, in turn mounted to thevehicle. A top surface of the housing 12 includes an opening 17 throughwhich an antenna 18, or a portion thereof is connected. If the housing12 is mounted within a separate enclosure, an external antenna, notshown, may be mounted to the enclosure and an electrical conductor maybe connected in series between the external antenna and a connectorextending through the opening 17.

The housing 12 includes at least one opening 19 on a front surfacethrough which a display 30 and a user interface 34 are accessible to anoperator. Optionally, multiple openings 19 may be provided, includingseparate openings for the display 30 and the user interface 34 or forcomponents of the user interface 34. The display 30 provides, forexample, graphical as well as alpha-numeric indication of the status ofthe controller 10, including, but not limited to, parameter values,configuration of the controller 10, battery life, strength of the signalbeing received, magnitudes of input/output signals, and warning or faultmessages.

The user interface 34 is configured to receive input from the operator.According to one embodiment of the invention, the user interface 34includes four push buttons 36. The push buttons 36 allow the operator toscroll up or down, enter data, or return to a previous entry.Optionally, any suitable number of buttons 36 or other input devices maybe provided in the user interface 34 according to the systemrequirements. The user interface 34 also includes a pair oflight-emitting diodes (LEDs) 35 which provide a visual indication ofwhether a fault exists, whether the controller 10 is powered up, andwhether the controller 10 is communicating with a transmitter.

Referring also to FIG. 2, the housing 12 includes two openings 41through which connectors for input and output terminals 44 extend.Optionally, the housing 12 may include either a single opening 41 ormore than two openings 41 for terminals 44 according to the applicationrequirements. The terminals 44 provide a connection to the inputs andoutputs, a portion of which are configurable.

Referring next to FIG. 3, an exemplary application of the controller 10includes a hydraulic valve block 50 connected to the controller 10. Thehydraulic valve block 50 controls distribution of hydraulic fluid to thevarious hydraulic motors, pumps, and pistons used to move the hydraulicequipment. An input line 54 establishes fluid communication between areservoir and the valve block 50. Valves, controlled by solenoids 52,regulate the flow of hydraulic fluid between the input line 54 and eachoutput line 56 to the hydraulic devices. The solenoids 52 receivecontrol signals via electrical conductors 22 connected between theterminals 44 of the controller 10 and each solenoid 52. The conductors22 may be separate conductors for each solenoid 52, an industrialnetwork medium, or any other suitable conductor 22. A return conductor23 may be included from each solenoid 52 to the controller 10. Thereturn conductor 23 may carry signals indicating, for example, thestatus of a valve or the magnitude of a current flowing through asolenoid. A transmitter 60 is configured to accept commands from anoperator via input devices 62 and transmit control signals responsive tothe commands wirelessly to the receiver.

Referring next to FIG. 4, the controller 10 incorporates a receiver 21,the display 30 and user interface 34, along with a processor 20 tocontrol hydraulic equipment. The receiver 21 includes the antenna 18 anda receiver circuit. According to one embodiment, it may be desirable forthe controller to transmit, for example, a watchdog signal or a statussignal to the transmitter circuit. Consequently, the receiver circuitmay be integrated into a transceiver circuit 14. Optionally, separatetransmit and receive circuits may be provided. An electrical conductor16 connects the antenna 18 to the transceiver circuit 14. Thetransceiver circuit 14 communicates command signals received at thecontroller 10 to the processor 20.

The processor 20 is operatively connected to the memory device 26. Theprocessor 20 may include a single processor or multiple processorsoperating independently or in parallel and connected in any manner knownin the art. Similarly, the memory device 26 may include either a singledevice or multiple devices. Multiple devices may be interconnected via abus or separately addressed as is known in the art. The memory device 26stores the program, which consists of a series of processor executableinstructions. The processor 20 executes the instructions to control themobile hydraulic equipment. The memory device 26 also stores parametersused to configure the controller 10. The processor 20 reads the valuesof stored parameters for use during execution of the program.

The processor 20 is operatively connected to the display 30 and the userinterface 34 for configuration of the controller 10. Referring also toFIG. 5, the parameters may be arranged in a menu tree 100. The currentsettings of a parameter are shown on the display 30, and an operatorpresses the push buttons 36 to scroll up or down, enter data, or returnto a previous entry. Optionally, configuration of the terminals 44 maybe performed via a remote device, such as a computer connected throughone of the communications ports, 70-72. For example, it may be desirableto perform an initial configuration by connecting a computer to the USBport 70. A program executing on the computer may be used to transfersettings for each of the parameters in the controller 10 configuringeach of the terminals 44.

In operation, the controller 10 receives commands from the transmitter60 to control the mobile hydraulic equipment. The control signals arereceived at the antenna 18 and converted by the transceiver circuit 14into signals to the processor 20. The processor 20 executes the programto convert the control signals received from the transceiver circuit 14to desired command signals for output at the terminals 44, according tothe configuration of the terminals 44 defined, at least in part, by theparameter settings.

The terminals 44 may be selectively configured for one of multiple modesof operation. According to one embodiment of the invention, a firstportion 46 of the terminals 44 may be configured in a first mode toreceive an analog input signal and in a second mode to receive a digitalinput signal. A single electronic circuit accepts either the analogsignal or the digital signal from the terminal 44. The electroniccircuit includes an analog-to-digital converter which converts themagnitude of the voltage present at the terminal 44 to a digital valuereadable by the processor 20. If the terminal 44 is configured toreceive an analog signal, the processor 20 executes the control programresponsive to the digital value corresponding to the magnitude of thevoltage present at the terminal 44. If the terminal 44 is configured toreceive a digital signal, the processor 20 converts the digital valuefrom the analog-to-digital converter to a logical “1” when the magnitudeof the voltage is greater than a first threshold voltage, such as threevolts, and converts the digital value to a logical “0” when themagnitude of the voltage is less than a second threshold voltage, suchas two volts. Optionally, the first and second threshold values may bethe same value or they may be selected at another value according to thesystem requirements.

A second portion 48 of the terminals 44 may be configured in a firstmode to receive an input signal and in a second mode to transmit anoutput signal. Each terminal 44 of the second portion 48 includesparallel circuits selectively active according to the configuration ofthe terminal 44. One of the parallel circuits is configured to receivethe input signal and the other of the parallel circuits is configured totransmit the output signal, and only one of the circuits is operativelyconnected to the terminal 44 at a time as selected by a configurationparameter for each terminal 44.

Each of the parallel circuits is further configured to selectivelyoperate in multiple modes. The input circuit may be configured, forexample, in a first mode to receive a digital input and in a second modeto receive a frequency input. A representative frequency input is apulsed input, such as a pulse train output from an encoder, where themagnitude of the input signal alternates between a logical one and alogical zero. The output circuit may be configured to operate, forexample, in one of three modes. First, the terminal 44 may be configuredto provide a pulse-width modulated (PWM) signal. The PWM output signalalternates between zero volts and a reference voltage supplied to theterminal 44. The processor 20 executes to determine a desired duty cycleof the output signal, as a percentage of a fixed time period. The outputsignal remains on for the desired percentage of the period and off theremainder of the period. Second, the terminal 44 may be configured as adigital output signal. The terminal 44 operates in a similar manner tothe PWM output signal with the processor 20 setting a 100 percent dutycycle to output a logical “1” and setting a zero percent duty cycle tooutput a logical “0”. Third, the terminal 44 may be configured toprovide a current compensated output signal. When a terminal 44 isconfigured to provide a current compensated output signal, another ofthe terminals 44 serves as a return terminal. A PWM signal is againoutput from the configurable terminal 44, and the magnitude of a currententering at the return terminal is measured. The controller 10 comparesthe measured current to a desired current and adjusts the duty cycle ofthe PWM signal responsive to a difference between the two signals.

For hydraulic control, it is often desirable to have a pair of valvesand solenoids 52 for each controlled member. A first valve is controlledto supply hydraulic fluid to the member, for example, to extend theboom, and a second valve is controlled to return hydraulic fluid to thereservoir, for example, to retract the boom. Consequently, a portion ofthe configurable terminals 44 are configurable as paired outputs and areinterlocked such that only one of the pair of terminals 44 may output acontrol signal at a time.

Optionally, the controller 10 may be configured to communicate via anindustrial network such as the controller-area network (CAN). A firstnetwork interface 71 and a second network interface 72 are operativelyconnected to the processor 20. A hydraulic valve block 50 may similarlybe configured to communicate via a CAN network. The processor 20executes to encapsulate the control signals for each of the solenoids 52into the designated network protocol or message format and transmits thecontrol signal to the valve block 50.

The processor 20 may further execute to compensate an output signalresponsive to an ambient temperature in which the controller 10 isoperating. The processor 20 receives a temperature signal from atemperature sensor 32, and determines a multiplier as a function of thetemperature signal. The multiplier may be calculated, read from a tableof values stored in the memory device 26, or a combination thereof. Theprocessor 20 then compensates the control signals to be output to thesolenoids 52 as a function of the multiplier. The multiplier may beapplied to command signal received from the transceiver circuit 14, tothe duty cycle command at an output terminal 44, or an intermediatevariable stored within the processor 20 and used during execution of theprogram. The compensated control signals are then output at theappropriate terminals 44.

It should be understood that the invention is not limited in itsapplication to the details of construction and arrangements of thecomponents set forth herein. Variations and modifications of theforegoing are within the scope of the present invention. It also beingunderstood that the invention disclosed and defined herein extends toall alternative combinations of two or more of the individual featuresmentioned or evident from the text and/or drawings. All of thesedifferent combinations constitute various alternative aspects of thepresent invention. The embodiments described herein explain the bestmodes known for practicing the invention and will enable others skilledin the art to utilize the invention.

1. A controller for mobile hydraulic equipment, comprising: a housing; areceiver mounted at least partly within the housing and configured towirelessly receive a plurality of transmitted control signals; aprocessor mounted within the housing and operatively connected to thereceiver to receive the control signals and generate a plurality ofoutput signals for operating the mobile hydraulic equipment; a memorydevice mounted within the housing and operatively connected to theprocessor, the memory device storing at least one parametercorresponding to control of the mobile hydraulic equipment; a displaymounted to the housing and operatively connected to the processor, thedisplay configured to provide a visual indication to an operator of atleast one parameter corresponding to control of the mobile hydraulicequipment; and a user interface mounted to the housing and configured toreceive input from the operator to adjust the parameter on the display.2. The controller of claim 1 further comprising a plurality of terminalsoperatively connected to the processor and selectively configured tooperate in one of a plurality of modes, wherein the memory device storesat least one parameter corresponding to each terminal and wherein theparameter is adjustable from the user interface to select the operatingmode.
 3. The controller of claim 1 wherein the user interface is aplurality of buttons accessible to the operator through at least oneopening in the housing.
 4. The controller of claim 2 wherein a portionof the terminals are selectively operable in a first mode to receive ananalog signal or a second mode to receive a digital signal.
 5. Thecontroller of claim 2 wherein a portion of the terminals are selectivelyoperable in a first mode to receive an input signal and selectivelyoperable in a second mode to transmit an output signal.
 6. Thecontroller of claim 5 wherein, in the first mode, the terminals areselectively operable to receive one of a digital input and a frequencyinput and, in the second mode, selectively operable to transmit one of acurrent compensated output, a pulse width modulated output, and adigital output.
 7. The controller of claim 2 wherein a portion of theterminals are configured as paired outputs, wherein only one of thepaired outputs may output a signal at a time.
 8. The controller of claim2 further comprising a temperature sensor providing a signal to theprocessor corresponding to an ambient temperature at the controller. 9.The controller of claim 8 wherein a portion of the terminals areconfigured to provide an output signal compensated as a function of theambient temperature.
 10. A controller for mobile hydraulic equipment,comprising: a housing; a receiver mounted at least partly within thehousing and configured to wirelessly receive a plurality of transmittedcontrol signals; a processor mounted within the housing and operativelyconnected to the receiver to receive the control signals and generate aplurality of output signals for operating the mobile hydraulicequipment; a temperature sensor providing a signal to the processorcorresponding to an ambient temperature at the controller. and aplurality of terminals operatively connected to the processor andselectively configured to operate in one of a plurality of modes,wherein a portion of the terminals are configured to provide an outputsignal compensated as a function of the ambient temperature.
 11. Thecontroller of claim 10 wherein a portion of the terminals areselectively operable in a first mode to receive an analog signal or asecond mode to receive a digital signal.
 12. The controller of claim 10wherein a portion of the terminals are selectively operable in a firstmode to receive an input signal and selectively operable in a secondmode to transmit an output signal.
 13. The controller of claim 10wherein a portion of the terminals are configured as paired outputs,wherein only one of the paired outputs may output a signal at a time.14. The controller of claim 10 further comprising: a display mounted tothe housing and operatively connected to the processor, the displayconfigured to provide a visual indication to an operator of at least oneparameter corresponding to control of the mobile hydraulic equipment; auser interface mounted to the housing and configured to receive inputfrom the operator to adjust the parameter on the display.
 15. Thecontroller of claim 13 wherein the user interface is a plurality ofbuttons accessible to the operator through at least one opening in thehousing.
 16. A controller for mobile hydraulic equipment, comprising: ahousing; a receiver mounted at least partly within the housing andconfigured to wirelessly receive a plurality of transmitted controlsignals; a processor mounted within the housing and operativelyconnected to the receiver to receive the control signals and generate aplurality of output signals for operating the mobile hydraulicequipment; a display mounted to the housing and operatively connected tothe processor, the display configured to provide a visual indication toan operator corresponding to control of the mobile hydraulic equipment;a plurality of buttons accessible to the operator through at least oneopening in the housing and configured to receive input from the operatorto adjust control of the mobile hydraulic equipment; and a plurality ofterminals operatively connected to the processor and selectivelyconfigured to operate in one of a plurality of modes, wherein the modeis configured from the user interface.
 17. The controller of claim 16further comprising a temperature sensor providing a signal to theprocessor corresponding to an ambient temperature at the controller. 18.The controller of claim 17 wherein a portion of the terminals areconfigured to provide an output signal compensated as a function of theambient temperature.
 19. The controller of claim 16 wherein a portion ofthe terminals are selectively operable in a first mode to receive aninput signal and selectively operable in a second mode to transmit anoutput signal.
 20. The controller of claim 16 wherein a portion of theterminals are configured as paired outputs, wherein only one of thepaired outputs may output a signal at a time.